1. Technical Field
The present disclosure relates to a light-emitting device, and in particular to a light-emitting device comprising a contact structure.
2. Description of the Related Art
The light-emitting diodes (LEDs) of the solid-state lighting elements have the characteristics of the low power consumption, low heat generation, long operational life, shockproof, small volume, quick response and good opto-electrical property like light emission with a stable wavelength, so the LEDs have been widely used in household appliances, indicator light of instruments, and opto-electrical products, etc. As the opto-electrical technology develops, the solid-state lighting elements have great progress in the light efficiency, operation life and the brightness, and LEDs are expected to become the main stream of the lighting devices in the near future.
Generally speaking, an operation voltage of a light-emitting device is an important parameter in the lighting devices. If the operation voltage is too high, some adverse effects such as high power consumption or low light efficiency are occurred. Therefore, there is a need for reducing the operation voltage of the light-emitting device.